In this retrospective study, the authors monitored the patient health coverage in 6 Rwandan hospitals in the period between 2011 and 2014. Among the 6 hospitals, 2 are third level hospitals, 2 district hospitals and 2 private hospitals. Patient insurance and financial data were extracted and analyzed from OpenClinic GA, an open source hospital information system (HIS) used in those 6 hospitals. The percentage of patients who had no health insurer globally decreased from 35% in 2011 to 15% in 2014. The rate of health insurance coverage in hospitals varied between 75% in private hospitals and 84% in public hospitals. The amounts paid by the patients for health services decreased in private hospitals to 25% of the total costs in 2014 (-7.4%) and vary between 14% and 19% in public hospitals. Although the number of insured patients has increased and the patient share decreased over the four years of study, the patients' out-of-pocket payments increased especially for in-patients. This study emphasizes the value of integrated hospital information systems for this kind of health economics research in developing countries.